Combination string plate and string tension maintaining mechanism



Oct. 18, 1966 R. A. BROCATO 3,279,298 COMBINATION STRING PLATE ANDSTRING TENSION MAINTAINING MECHANISM Filed Jan. 11, 1963 2 Sheets-Sheet1 Oct. 18, 1966 R. A. BROCATO 3,279,298

COMBINATION STRING PLATE AND STRING TENSION MAINTAINING MECHANISM FiledJan. 11, 1963 2 Sheets-5heet 2 INVENTOR Fofizr/ 4 fir'dca/o UnitedStates Patent 3,279,298 COMBINATION STRING PLATE AND STRING TENSIONMAINTAINING MECHANISM Robert A. Brocato, 2213 Fairfield Ave.,Shreveport, La. Filed Jan. 11, 1963, Sex. N0. 250,814 Claims. (Cl.34-208) This invention is concerned with string plates and stringtension maintaining mechanisms. This invention is an improvementespecially important to pianos.

In conventional pianos there is a piano string plate and pin-block. Inthe invention to be discussed the string plate has been drasticallymodified from the conventional type which has been used unchanged foryears. This invention is a piano string plate which is so designed thatthe tension of the strings will be maintained without the use of apin-block or the heavy wood beams that lie behind the plate. Eliminationof the beams would result in a lighter piano and a shorter piano depthby about seven inches in the vertical types, and a corresponding smallerthickness in the horizontal types. The invention will be especiallyadaptable to very small or portable pianos where the size and weight areinherently important. Another advantage of the invention is that thetension maintaining mechanism will not have the pitfalls of theconventional pin and block arrangement. In the invention there will beno tuning pins to slip, and the process of tuning the piano will begreatly speeded up. The invention has not only an application to pianos,but it may be used in other musical instruments that use strings. Theinvention would be especially adaptable to harps.

Further objects and advantages of the invention will become apparent inthe course of the following detailed description when viewed togetherwith the accompanying drawings of the string plate and tensionmaintaining mechanism. In the drawings:

FIG. 1 is a side view of a vertical piano which is utilizing theinvention described herein. Part of the piano case has been cut away toshow the tension maintaining mechanism more clearly.

FIG. 2 is a front view on an enlarged scale of a detailed section of thetop of the piano string plate invention. This is the part of the platewhich is designed to maintain string tension.

FIG. 3 is a top plan view on an enlarged scale of the detailed sectionof the string plate.

FIG. 4 is a side view on an enlarged scale of the detailed section ofthe string plate.

Referring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, FIG. 1 is especiallydrawn for the sake of illustration so that only one string is visible inthe drawing. It can be observed here in FIG. 1 that the piano plate thatis proposed herein is identical with an ordinary plate except on the topportions where the conventional pin-block was located. The proposedpiano string plate has at the extremities of the strings, a U-beam ortrough-like construction 4, the trough running along the outer edge ofthe plate. In vertical pianos, the trough 4 will be at the top of thestring plate 1. The trough or channel 4 will have at the outermost sidea flange or wide rim 7. A hole is drilled between the sides of thetrough in which a bolt 6 is placed. Bolt 6 has a hole drilledtransversely directly through the head, similarly to an eyebolt. Thediameter of the hole is such that it is just larger than the diameter ofthe piano string 2.

Because there is not now any type bolt used in piano plate construction,bolt 6 does not have an accepted name. Here bolt 6 will be called thefinal or concert tuning bolt.

The hole in trough 4 for the final or concert tuning bolt 6 has beencarefully positioned so that string 2 will line up with the conventionalpiano action 8 in a correct manner.

Bolt 5 located in a hole drilled in flange 7 will be called the primaryor rough tuning bolt. The construction of primary tuning bolt 5 can bestbe seen in FIG. 2 where one of the primary tuning bolts 5 is drawn outof its hole. It will be noticed that the primary tuning bolt 5 has ahole drilled in it just underneath the bolthead. The hole isperpendicular to the bolt and of diameter just larger than that ofstring 2. Primary tuning bolt 5 is located in a hole in flange 7. String2 passes transversely over the inner side of trough 4 through the holein the head of final tuning bolt 6, over the outer side of trough 4 andthrough the hole in primary tuning bolt 5. Since the string goescompletely through the primary tuning bolt 5, the tension of the stringmay be adjusted by turning primary tuning bolt 5, similarly to theconventional piano tuning pins. The tension on the string should be onlyslightly taut. Then the nut on primary tuning bolt 5 is tightened. Thispresses the bolthead upon the string 2 against the flange 7, therebymaintaining a mildly taut tension on the string. At this stage the nuton final tuning bolt 6 is tightened until the desired concert tension ofthe string is reached. The tension of the strings is easily adjusted inthis manner because final tuning bolt 6 has only a small component oftension pulling on it, and also the adjustment by means of the finaltuning bolt is not at all a critical one.

When the string is once in correct adjustment at the factory allsubsequent tunings will be done by adjusting final or concert tuningbolt 6. Primary tuning bolt 5 will probably never have to be loosenedagain unless is is to replace the string.

In FIGS. 2, 3, and 4 is illustrated a detailed section of the tensionmaintaining device of the piano plate. In most pianos all of the keys,except the bass keys, strike three strings tuned in unison. FIGS. 2, 3and 4 illustrate the three strings of one note being held in tension. Itcan be observed from FIG. 2, the front view of the device, that thefinal tuning bolts 6 are not in a straight line but are staggered. Alsothe primary tuning bolts can be seen in FIGS. 3 and 4 to be accordinglystaggered along the flange of the trough. This is to assure properclearance for a socket wrench to fit on the bolts, as the strings inFIGS. 2 and 3 are very close together in conventional pianos.

The proposed invention completely eliminates the need for a pin-block.The heavy wooden back beams may be eliminated also, but the piano stringplate should have several ribs runnnig in the same direction as thestrings, on the front side of the plate, and several inches in depth insuch a manner that the piano string plate will not have a tendency tobecome bowed in the absence of the back beams. A plate strengthening rib3 can be seen in FIGS. 1, 2 and 4.

Several embodiments of the invention have been described, but changesand modifications can be made without departing from the invention asdefined in the claims.

I claim as my invention:

1. In a musical instrument having strings, an apparatus to adjust thetension on the strings consisting of a U-beam, trough or channel withbolt holes through the bottom of the U-beam, trough or channel, eyeboltsconstructed so that the eye or opening of the eyebolt is slightly largerthan the diameter of the strings, said eyebolts being placed in the boltholes of the U-beam, trough or channel so that the eye is in the valleybetween the sides of the U-beam, trough or channel and so that the endsopposite the eyes pass completely through the bottom of the U-beam,trough or channel and a nut is screwed on each eyebolt, adjustment ofthe string tensions being made by turning the nuts on said eyebolts.

2. In a musical instrument having strings, an apparatus to hold thestrings in tension and attain precise tuning of the strings consistingof; an elongated or strip-like flat plane located at one end of thestrings, the elongated or strip-like flat plane has bolt holes built init, the arrangement of the bolt holes is such as to conform to thedesired alignment of the strings, in the bolt holes fit special bolts soconstructed such that there is a hole or opening passing transverselythrough the body of the bolt directly beneath the bolt head, thediameter of this hole or opening is slightly larger than the diameter ofthe strings, a nut is fastened on the bolt against the side of theelongated or strip-like flat plane opposite the bolt head, each stringis connected to the appropriate special bolt by passing that stringcompletely through the hole or opening beneath the head of the bolt soas to coil the string, to some extent, around the body of the bolt, thetension is attained by turning the special bolt so as to tighten orslacken the string and the nut is tightened on the bolt in this positionto maintain the tension; means to attain precise tuning of each stringutilizing a U-beam, trough or channel mostly under the string array, ina transverse manner to the strings and between the said elongated orstrip-like flat plane and the string ends opposite to those whichterminate at the said elongated or strip-like flat plane, the U-beam,trough or channel has eyebolts passing through holes in the bottom ofthe U-beam, trough or channel and substantially perpendicular to theU-beam, trough or channel so that the eye is on the concave side of theU-beam, trough or channel and a nut is fastened to the eyebolt on theother side of the U-beam, trough or channel, precise adjustment of thestring tensions being made by turning the nuts on the eyebolts.

3. In a musical instrument having strings, an apparatus to hold thestrings in tension and attain precise tuning of the strings consistingof; an elongated or strip-like flat plane located at one end of thestrings, the elongated or strip-like plane has bolt holes built in it,the arrangement of the bolt holes is such as to conform to the desiredalignment of the strings, in the :bolt holes fit special bolts soconstructed such that there is a hole or opening passing transverselythrough the body of the bolt directly beneath the bolt head, thediameter of this hole or opening is slightly larger than the diameter ofthe strings, a nut is fastened on the bolt against the side of theelongated or strip-like flat plane opposite the bolt head, each stringis connected to the appropriate special bolt by passing that stringcompletely through the hole or opening beneath the head of the bolt soas to coil the string, to some extent, around the body of the bolt, thetension is attained by turning the special bolt so as to tighten orslacken the string and the nut is tightened on the bolt in this positionto maintain the tension; means to attain precise tuning of each stringutilizing a U-beam, trough or channel mostly under the string array, ina transverse manner to the strings and positioned near the ends of thestring, in very close proximity to the said elongated or strip-like flatplane in such a manner that the said elongated or strip-like flat planelies in a longitudinal direction to the sides of the U-beam, trough orchannel and in sequence along the strings such that the said elongatedor strip-like flat plane is nearer to the closer ends of the stringsthan the U-beam, trough or channel, the U-beam, trough or channel haseyebolts passing through holes in the bottom of the U-beam, trough orchannel and substantially perpendicular to the U-beam, trough or channelso that the eye is on the concave side of the U-beam, trough or channeland a nut is fastened to the eyebolt on the other side of the U-beam,trough or channel, precise adjustment of the string tensions being madeby turning the nuts on eyebolts.

4. In a musical instrument having strings, a string tension maintainingapparatus comprising a U beam having a flange extruding outwardly fromone side thereof, eyebolts passing through holes provid-ed in the websection of said U-beam, the eyes. of said eyebolts being on the concaveside of said U-beam, a nut for each eyebolt on the opposite side of saidconnecting web section, special bolts extended through said extrudedflange, each special bolt having a transverse opening through the bodythereof directly beneath the head portion, said special bolts lying in aplane perpendicular to the plane of said extruded flange, nutsthreadedly engaging said special bolts, each of the above-mentionedbolts being aligned with the strings so that a single string will passthrough an eyebolt and through the opening of one of the special bolts,a rough tension for tuning being made by rotating the special bolt andsecuring its nut, and the final and precise tension for tuning beingmade by adjusting the height of the eyebolt with respect to theconnecting web of said U-beam.

5. In a musical instrument having strings which are held firmly at oneend, means for adjusting the tension of the strings comprising anelongated strip lying mostly transversely to the strings at theiropposite ends, bolt holes in said strip, said bolt holes in spacedalignment with said strings, special bolts positioned through said boltholes, each of said special bolts provided with a head and a threadedshank portion, a transverse opening through each bolt directly beneaththe head, the opening in each of said special bolts adapted to receivean end of one of said strings, each string being adapted to coil itselfaround the shank of said bolt upon rotation of the head thereof for thetightening and loosening of the tension on said string, a nut for eachbolt threadedly engaging the shank portion thereof and adapted to securethe bolt to said strip against rotation and consequently to maintain thestring at any chosen tension.

References Cited by the Examiner UNITED STATES PATENTS 6/1892 Felldin84-208 4/1901 White 84208 FOREIGN PATENTS 37,401 11/1886 Germany.

1. IN A MUSICAL INSTRUMENT HAVING STRINGS, AN APPARATUS TO ADJUST THETENSION ON THE STRINGS CONSISTING OF A U-BEAM, TROUGH OR CHANNEL WITHBOLT HOLES THROUGH THE BOTTOM OF THE U-BEAM, TROUGH OR CHANNEL, EYEBOLTSCONSTRUCTED SO THAT THE EYE OR OPENING OF THE EYEBOLT IS SLIGHTLY LARGERTHAN THE DIAMETER OF THE STRINGS, SAID EYEBOLTS BEING PLACED IN THE BOLTHOLES OF THE U-BEAM, TROUGH OR CHANNEL SO THAT THE EYE IS IN THE VALLEYBETWEEN THE SIDES OF THE U-BEAM, TROUGH OR CHANNEL AND SO THAT THE ENDSOPPOSITE THE EYES PASS COMPLETELY THROUGH THE BOTTOM OF THE U-BEAM,TROUGH OR CHANNEL AND A NUT IS SCREWED ON EACH EYEBOLT, ADJUSTMENT OFTHE STRING TENSIONS BEING MADE BY TURNING THE NUTS ON SAID EYEBOLTS.